Polar bears are perfectly suited for living in the extreme and unforgiving Arctic environment. They experience almost no heat loss; their long dense fur is hollow and translucent, acting as a remarkably efficient insulator against the bitter cold and wind. Where the fur is thinner, a maximum amount of heat from the sun is absorbed by the polar bear’s black skin. Their massive paws are covered with thick fur with only the pads exposed. In addition, the polar bear has up to an 11.5 cm (4.5 in) thick layer of fat to insulate it from the severe cold.